The flags are:

-xres <float> Set new X resolution

-yres <float> Set new Y resolution

-coding <string> Set coding - eg. NOCODING, LABPACK, etc.

-type <string> Set type - eg. B_W, XRAY, etc.

-format <string> Set format - eg. FMTUCHAR, FMTDPCOMPLEX, etc.

-xsize <int> Set new Xsize

-ysize <int> Set new Ysize

-bands <int> Set new Bands

See <vips.h> for a complete list of passible values for type, coding and format.

Be very careful when changing Xsize, Ysize, BandFmt or Bands. edvips does no checking!